Runoff
by saber-otter
Summary: My first TMNT fic! What happened to the ooze after Splinter and the Turtles left the scene years ago? A story written primarily for fun, but crtiques on my writing would be most appreciated. Last chapter 6 added. Thanks to all who have reviewed!
1. Prologue

The rain that had been threatening all day finally began in a steady drizzle. People on the busy New York streets ignored the light precipitation, though distant flashes in the night sky indicated the worst was yet to come. It took a while for the drizzle to soak the ground. When it did, the water began a slow, steady trickle into the storm drains…

The sewers were surprisingly dry for that time of year. One tunnel near the surface had a mess of glowing green ooze on its floor. Week-old tracks of some turtles and a solitary rat led from it where, in a normal year, the ooze might have been washed away by now. The rainwater dripped down the drains and began its flow down the dry sewer - lifting the ooze and taking it along with the flow.

A young turtle, only a few months out of the egg, ambled down the dark sewer. It was unclear when the first few box turtles had managed to fall through the storm drains years ago, but since then a small population had managed to flourish. The little terrapin stopped to bite at a morsel that smelled like food. His eyes blinked hard several times and he quickly abandoned the effort. As he continued his travels, a shallow flow of water appeared behind him and pushed him forward. Being such a small turtle, the water continued to pull him as it flowed.

But was it water? It smelled strange. And it certainly _felt _strange - his scaled skin tingled at its touch. Desperately, the little brown turtle scrabbled at the floor as it passed beneath him. He wanted to escape this odd water.

Above ground, a bright flash and thunderous crack heralded the approach of a severe thunderstorm. Raindrops the size of cherries fell in a torrent. People walking on the sidewalks ran for cover; cars on the streets turned their windshield wipers to the highest setting.

The water running down the sewers soon reflected this change. The little turtle found that his feet no longer touched bottom when he kicked and struggled. Before long, his small pipe joined with a much larger one. He fell over a small ledge and found himself in a raging torrent fed by many small pipes. At speeds he had never experienced, he was whisked down the large tunnel. Yet his mind was almost too simple for fear - he only knew that he wanted to get back on firm ground… and that the mysterious burning on his skin had finally stopped. What he didn't know was the source of his discomfort had been diluted beyond the point of effectiveness.

A slight dip sent him underwater for two or three seconds; the pipe he was in had joined an even larger one. Now the flow went much faster. The young turtle kicked madly with his little legs, trying to get out of the current and over to the side. He was barely moving except for forward with the flow, but he tirelessly kept at it. Suddenly, he was sent spinning. He'd escaped the main current and was washed into a short, dead-end tunnel. The water calmed rapidly, and the little turtle was able to swim until he could finally touch the floor. The ground was covered in garbage, and a storm drain leading to the outside was fixed in the wall above. There was plenty to eat among the garbage, which was lucky; the water only flowed into this tunnel and would be too difficult to swim against.

The little terrapin lived in the dead-end tunnel for several months. The garbage that was constantly being chucked down the storm drain was the result of nearby snack vendors on street level, as well as the apparent unavailability of trash cans. Therefore, the turtle was always fed. As time went on, he became more aware of his surroundings. He even started trying to imitate snatches of sounds he heard from the creatures who lived above.

He had no idea that he had become different until one of his own kind appeared in his tunnel. He recognized the creature and could tell by its markings that it was quite an old turtle. And yet… he picked it up and inspected it. It was much smaller than he, and its arms and legs were shaped very differently. He tried to talk to it, using sounds he'd learned from the world above the storm drain. It acted as if he wasn't there. When he touched it, it _hid_ from him! The young turtle was confused and lost. What had he become then, if he wasn't the creature he'd been born as?

His stomach growled. For the past week or so, the food thrown down the storm drain had not been enough for him and his healthy appetite. He knew that to survive, he'd have to find a better place. The turtle stood and carried his cousin to the end of the tunnel. He set it in the water, curiously gazing at his own legs after it'd swum away. The water only came to his knee nowadays; he remembered it being much deeper… Putting this out of his mind, the young terrapin began splashing down the larger tunnel.

A hole in the ceiling intrigued him, and he figured out how to use the ladder within five minutes. As his head popped above street level, the man who had been just about to climb down the manhole jumped back. "Augh! Look, guys - a slimy freak!"

Another man standing nearby elbowed a third worker. "See what I mean? Told y'all the sewers were gonna be the government's new nuclear waste dump. We'll all be dead or look like that in a coupla years…"

The turtle, perplexed, climbed out of the hole and began making sounds he'd heard the snack vendors use to calm angry clients. "What if I give ya a partial refund? I'll give ya another f'r free… How 'bout a soda? On the house."

But far from calming the workman, it only seemed to excite him more. "He's talking complete nonsense - crazy as they come! Quick, hand me that sledgehammer…"

The young shellback decided that the odd creatures must be afraid of him, and he ran wobbly into an alley. Once there, he stretched his legs a bit. They were unused to strain after his life in a small tunnel, but he needed them. He looked around, unsure of what to do. Where would he go? Where could he find food?

He took a deep breath. Slowly he became aware of a smell in the air that his turtle instincts were labeling as "food." Fine. He'd just follow that…

The brown turtle spent the rest of the afternoon going from hiding place to hiding place. He quickly learned not to be seen after someone took a few swings at him in the street. As he ran, he realized something strange. Before he'd been trapped in that sewer tunnel months ago, he'd always had to take long rests after any sort of physical exertion. But now, he was able to keep running…and running! When he did so for long periods of time, he became hot inside and his skin was inexplicably wet. What had happened to him? He'd been born a turtle but was now halfway between turtle and something like these odd creatures that roamed the surface! After all, he had a similar build to theirs - his limbs were nearly the same shape - but he still carried a shell on his back! A shell which he found could no longer hide him when he was in peril.

At long last, his senses led him to an enormous body of water, which he managed to spot about a quarter mile before he got there. After a half hour of alley-weaving, he set foot on a dock for the first time and surveyed New York Harbor by the light of the setting sun. The water appeared chock-full of swimming creatures that should do nicely for food. Upon further inspection, the turtle found that it was no good for drinking, but this didn't worry him. During his travels that day he'd managed to locate several nearby sources of fresh water. And as he paced across and studied the dock, he could already see how he could build himself a secret home in the air pocket underneath. It looked as if he'd found the right place for himself.

END PROLOGUE


	2. Chapter 1

For the first chapter I forgot a disclaimer, so here goes: **The TMNT belong to Mirage Studios, regrettably. I don't own 'em and I'm not earning anything from this little fanfic. My little brown turtle (will be named in a later chapter), however, is my own creation.**

Oh, and this is a pretty short chapter - my apologies._

* * *

_

_Plunk! _

Ripples disturbed the surface of the water, barely audible except to trained ears. In the dark, the shape of a giant humanoid turtle clung to the side of the dock. Slowly he lowered himself into the water, leaving his strung bow and quiver lying on the wooden surface

Shortly he climbed back up with his prize - a large fish with an arrow through it. Over the years, the young turtle had grown to adolescence. He had finally learned English from passersby, and named himself Mud because it was the color of his skin. He lived in the little shelter he'd built beneath the surface of the dock. The idea for the bow had come when he'd scavenged a _Bow Hunting _magazine out of the trash a few years back. He now used it to hunt, and his aim was becoming excellent.

Mud unstrung his bow and carried it over his shoulder with four large fish in his other arm. He was headed toward a hidden spot on the shore, where he could build a fire without fear of burning his home or being seen.

Suddenly he stopped and looked up. Was that a dark shape moving on a nearby rooftop? The brown turtle stared hard at the small, squat building, then resumed walking. _Must be my imagination_, he decided. Several paces later, he froze. There had been a suspicious noise. Mud stood still and strained his ears, trying to catch it again.

_THUD!_

The turtle went sprawling forward; he dropped his fish and only barely kept hold of his bow. He scrabbled upright, clutching the weapon. Before him were six humans clad in black and wearing hoods. Their clothing was emblazoned with an odd red shape. "What was _that_ for!" Mud demanded.

"Surrender, turtle!" growled one of the men.

Mud noticed that he, like the others, carried two dangerous-looking swords. Common sense told him to comply, but he was confused. "Surrender? Why are you attacking me?"

The man remained silent and glanced at one of his fellows uncertainly, then back at Mud. "You're coming with us," he stated firmly.

Mud couldn't help but laugh, even in the face of these dangerous-looking humans. "What kind of idiot do you think I am? You've attacked me, made me drop my dinner, and now you expect me to come with you like it's all okay?"

"Take him," barked the man to his companions, who leaped at Mud.

The turtle swung his bow madly like a staff; it was nearly straight when unstrung. But his frenzied thwacking could not match the training of the black-robed humans. A sword flat smashed into the back of his skull, and the world went dark.


	3. Chapter 2

**Author notes!**

I got a comment that Mask learning bowmaking from a magazine seems a bit farfetched. You may be overestimating his bow - I imagined he got the _idea_ from the magazine, but essentially uses a string tied to a stick. Not too spifftacular, but I've made 'em before and I'm sure you could get accurate with practice. Especially since he's been at it for several years. Thanks for noting that, though.

Oh, and for Lunar-ninja... I've had my "saber-otter" account for a year, before I started writing TMNT. Sorry for the confusion.

Now, back to the story! The TMNT and related characters still don't belong to me! 'Cept for my little turtle dude!

* * *

Mud slowly opened his eyes. He was in a dim room, the only flickering light coming from a pair of torches at the opposite end. The turtle was confused at first, but slowly the details of the strange ambush came filtering back into his head. 

Quickly he sat up on the small cot, but fell back clutching his skull. "Cursed…humans," he hissed, the headache reminding him harshly of that final blow.

"You're awake," observed a low, almost harsh voice.

Ignoring the throbbing, Mud sat up again and glared across the room, trying to penetrate the weak light. "Who's there?"

"It is only I," came the voice again.

This time Mud could tell it was coming from the shadows to his left. He looked over but could only pick out a dim figure in the gloom. "I'm in no mood for games," the turtle said firmly. "Just why was I brought here? Seems odd that there are bands of men runnin' around at night in New York City - armed to the teeth, no less!"

There was a brief flash, and a torch above Mud's cot blazed into life. The light revealed an Oriental man with an athletic build, clad in loose, white clothing. He was of average height, but hadquite a fewinches' advantage over Mud. "Why, you ask? Because there is a great danger in this town, a perilous enemy. They attack my operations without mercy, slaying many of my men. Four terrible monsters - with awesome fighting ability!" He sighed heavily. "Yes. Dangerous, indeed."

"Monsters, eh." Mud started to be incredulous, but then his gaze shifted to his own hand. Watching his three fingers as his hand balled into a fist, he shrugged. "I guess stranger things have happened in this town."

"My men tell me you are a reservoir of undeveloped talent," continued the man. "You scored quite a few hits before they could subdue you. If you are willing to give me your help, I can train you to fight… perhaps you can even help me slay my enemies."

Mud chuckled. "Be your hitman? No thanks. Why am _I _so important to this endeavor, anyway? Why haven't your men been able to deal with this so-called evil?"

The man shook his head sadly. "I forget you do not know the nature of the enemy. No, humans do not fare well against them. You, on the other hand, have mutated DNA in your cells. I admit I need someone like you to help me out, as your unusual DNA may give you just the edge you need."

Mud stared at his hand again. _Mutated DNA, huh? _he thought. _That could explain why I grew to look like a freakish turtle-man_. "I suppose I don't really have a choice, do I?" he said out loud.

"Suffice it to say that to turn down my offer would be a mistake," said the man with a dangerous look in his eyes.

Mud swung his legs over the side of the cot and stood up straight. "Then teach me."

The man bowed low. "Good. I am called Oroku Saki. And you?"

The turtle bowed in return. "I call myself Mud, sir."

"Mud?" chuckled Saki. "We'll find a warrior name for you when you're trained up a bit. Come." He led Mud out of the dimly-lit interrogation room and into a larger area with a higher ceiling. Racks on the walls held various weapons the brown turtle had never seen before. Saki motioned for him to stop, then approached one of the racks. When he turned around, he held a bow in his hands.

Mud stared at it - it was much nicer than his old bow had been. The wood was hard and polished, and the grip was wrapped in dark green. He explored the entire weapon with his hands when Saki handed it over.

"Let's see where you are with this bow, my friend," the man said, tossing a bowstring and quiver of arrows at Mud.

The turtle deftly strung the bow, and Saki's eyes showed approval. Mud easily nocked an arrow to the string and looked back at Saki. "What do you want me to shoot, sir?" he asked.

"Address me as _Master,_ young… er, turtle," corrected Saki. "Under me you will learn to fight as a ninja - remember that I am your Sensei."

"Sensei," began Mud again with a slight bow of the head. "What do you wish for me to shoot?"

Saki grabbed a tonfa from the wall and flung it into the open. "This!"

Mud sighted quickly and let the arrow fly. He sighed in disappointment as the arrow failed to stick in the wooden target.

Saki crossed the room and retrieved the tonfa. There was a shallow scratch near the middle where the arrow had grazed it. "You were only a bit off-target," he mused, "Unusual skill for being self-taught. My training will make you a deadshot. I also want to instruct you with this." The man turned to the wall again and came back holding a short sword. "This is called a wakizashi. Your bow is good for long distance attacks, but when the enemy comes up close, you'll need this."

Mud took the blade and swung it a few times experimentally. "Feels weird," he commented.

Saki chuckled. "You'll get comfortable using it with practice. Come. Let us begin."

* * *

"Ow!" 

"You must anticipate the next blow! Do not allow yourself to be surprised! And focus!"

_KLAK! K-KLAK!_ The turtle angled his bokken, fending off that of Saki's. Much had changed in the past two years. Beneath his brown skin rippled hard muscles from vigorous training. He was a bit taller than before, but at 5'5" he was still shorter than Saki and most of his men. He had been outfitted with clothing fit for a Foot turtle. His waist was belted with a strip of black leather, and crossbelts of the same material lay over his chest. His forearms and lower legs were wrapped in black cloth; on his head he wore a black skull mask with a blood-red Foot symbol emblazoned on the forehead. It was this latest accessory that had inspired the tougher name he'd given himself.

"Good swordplay, Mask!" grunted Saki as he blocked a swipe with some difficulty. With a twist of his bokken, the master disarmed his student. He bowed to the brown turtle and began to pace the room. "Mask - those demons in the city have become too dangerous."

"Have they, Master?"

"I am losing whole bands of Foot ninja to them every day as I try to find their hiding place," growled Saki. "This cannot continue! Mask, in the past two years I have concentrated on swordplay so you could at least wield your wakizashi competently against them. You are by no means a master, but you have a good chance of being able to survive."

Mask waited for Saki to get to the point, head bowed as he stood before his master.

"I would have liked to teach you kicks, throws, and punches in much more depth, but we would need more time. Time that we don't have the luxury of wasting. Mask, I want you to go into the sewers, where we believe them to be hiding. Take a band of ninja with you for backup. Be silent and swift, and try to snipe them with your bow. Only fight hand-to-hand if you must. You have come far in a short time, but your enemies have been training for much longer!"

The adolescent terrapin bowed low. "Tonight I will go out, my master."

Saki grunted with satisfaction and left the room.

Even along the busy New York streets, there were plenty of places the penetrating beams of car headlights did not illuminate. Only if one was looking specifically for them would one see the six or seven dark shapes that flitted from shadow to shadow and entered and alley.

Mask pried a manhole cover from its place and slipped into the tunnel silently, like a wraith. Once inside, he pulled the bow from one of the belts on his back and strung it. The quiver and his wakizashi sheath were bound together and strapped crosswise so they showed above his right shoulder. He grabbed an arrow now and nocked it to the string. "C'mon," he whispered to the others.


	4. Chapter 3

Leonardo blew out his candles and rose smoothly from the woven mat he used for meditation. He had risen early, as was his custom; the ten minutes' meditation was to be followed by his morning exercises in the dojo.

He was surprised to see the televisions on when he passed the entertainment center downstairs. "Mikey, what the - ? Were you up all night?"

Michelangelo's red-rimmed eyes stared glassily out of the holes in his orange mask. "Is it morning already?"

Leo glanced at the VCR clock to make sure. "Yes… it's just after six."

The orange-masked turtle yawned and pushed the start button on his controller to pause the game he'd been playing. "I suppose the good news is I finally beat that stupid werewolf boss. But man! I'm gonna be no good for training today."

If Mikey hadn't looked so tired, Leo probably would have made some comment on time management. As it was, he took pity on his brother and tossed a blanket to him. "Here. Rest up until Splinter calls us in. I'm going to work on that katana move I've been trying to get right."

"Could ya give me some of that energy? Please?" joked Michelangelo with a hint of irony in his voice. He pulled the blanket closer around him and settled in for some shuteye.

The bokken fell wide of the mark Leonardo had picked to strike. He growled, frustrated with his body's apparent inability to obey what he expected of it. With a sigh of resignation, he held the bokken so that it lay on its back, parallel with one of his sheathed katana. He furrowed his brow, concentrating.

"Hyaaah!" With a cry he leapt forward, acting as if he were unsheathing the bokken and turning the motion into a downward chop. This time, the blow fell diagonally across the dummy's neck.

"Well done, Leonardo."

The soft, hoarse voice surprised the young turtle. His head whipped around; he hadn't heard Splinter enter. "Sensei!"

"You are getting better, my son. But do not allow your concentration to completely block out the world around you. Be focused, but be aware. Had I been a Foot ninja, I might have slain you by now."

Leonardo bowed. "I will remember that, Master Splinter."

The old rat smiled. "Come, Leonardo. If my nose is not mistaken, your brothers have started breakfast."

As the two entered the dojo and entered the kitchen, the silence was broken by shouts.

"Geez, Raph! You broke the microwave again! I don't have _time_ to be fixing this whenever you use it!"

"Don't look at me, Donny! You wanna know why that piece of crap keeps bustin'? Cuz we got it from a _dump_, genius! _Someone _had to throw it out for it t'get there, and I wonder why!"

Leonardo and Splinter exchanged glances before going through the door. This was unusual - a fight between Raphael and Donatello? Usually the turtle in purple was much more patient with his hotheaded brother.

At any rate, Raph had somehow struck a nerve; Donatello's normally placid face was starting to tinge red as he retorted in a voice heavy with sarcasm. "Well, I'm _sorry_ I've been wasting my time on gadgets to keep our shells clear of those Foot psychos. I'm _sure_ we can sacrifice one or two of us if it means we'll have a working microwave!"

Splinter struck the tabletop with his walking stick. "Enough!" He pointed at the plate Raph was holding. "Raphael, what are you trying to do?"

The red-masked turtle nodded at the plate. "I was going to make bacon for breakfast, Sensei."

Splinter pointed his stick at the stovetop. "Use a pan, my son."

Leo poured a glass of water and gave it to Donatello. "Here, Don. If you want, I can offer a couple of extra hands to fix this after training. I may not understand all the technical stuff, but if you tell me what to do I can help. That way, you can get to your work much faster."

The water had been surprisingly refreshing - Don smiled slightly and nodded. "I'd appreciate that, bro." He glanced apologetically over at Raphael. "Sorry for losing it, Raph… I've had my hands full lately."

Raph looked up from his pan, which was beginning to sizzle. "No problem, Donny." He peered about the kitchen, "Now that the world is back in order… has anyone seen Mikey?"

"On the couch," replied Leo. "He says he was up late beating some wolf boss on that game of his. I told him to get some rest."

"No way!" exclaimed Raph. "He beat the Armored Werewolf in the Haunted Forest!" He practically vaulted out of the kitchen, heading for the TV room. "Yo, Mike!"

Splinter took over the pan of bacon. "I may give Michelangelo a reprieve for today, for I too am a little tired. Leonardo, you may take your brothers on a patrol of the sewers instead."


	5. Chapter 4

Just a friendly reminder that I don't own anyone but Mask! And now for Chapter 4!

* * *

In a murky side tunnel, a complaining whisper hissed in the darkness. "Ugh, I still can't sleep. Why did we have to spend the night in _this _dark hole?"

The noise woke Mask, who swung out at the air bad-temperedly. "Shut up! We had to bed down here because you idiots didn't find anything last night! Now get up; it's time to move, and keep your wits about you, eh?"

"Lead on, Mask," answered a surly voice, laden with exaggerated respect. While their terrapin leader was apparently comfortable in the sewers, the human Foot ninja were just hoping they'd find their quarry so they could leave.

They made their way down the dripping tunnel, light splashes the only sound they made. Without warning, a voice echoed from up ahead. "Man, I sure am lucky! Thought I was gonna get my shell kicked today."

A deeper growl of a voice replied, "An' you still might _get_ it kicked if you don't shut up, Mikey."

Mask held out a hand to halt the others. He strung his bow and readied an arrow, sighting down the long tunnel toward the noise. It was especially dark in this section of the sewer - the only light came from a storm drain about fifty yards ahead. He bent his bow and waited.

"Watch the light, guys." Another voice, this one tinged with authority. The Foot turtle watched four green creatures slip through the light, but he couldn't tell exactly what they were. All Saki had disclosed about their nature lay in his frequent comments about their similarities to Mask, and how it would help him in the eventual conflict. Not that it mattered exactly _what _they were, until they'd been neutralized. The brown turtle sighted on one of the backlit silhouettes and let fly.

Donatello had felt oddly uneasy during the entire patrol - so uneasy that he'd taken out his bo after only a few minutes of walking. After skirting the light beam, he brought his bo back up, walking quickly and holding it at the ready. The staff suddenly vibrated violently in his hands, and he nearly dropped it. Don squinted at what the light at his back revealed in the semi-gloom… an arrow, lodged in the wood! "We're being sniped, guys!" He dove to the side as another shaft whistled by, where his head had been a second earlier.

Leonardo looked up - his eyes were readjusting to the darkness and he could tell there were dark shapes ahead. "Don't present yourself as a target! They're up ahead; take 'em down!"

Mask had the tail of another arrow in his fingers, but his opponents were charging too fast for him to get off a shot _and_ be able to fight when they arrived. The turtle cast his bow aside and drew his wakizashi. "They're too close. Attack!" The Foot ninja leapt forward to attack, driving their four enemies back - almost to the beam of surface light.

Mask ducked a bo strike and slipped behind the four creatures. The brown turtle spun, slashed, and felt his blade catch on something. His eyes traveled slowly up the body of his opponent. It was a humanoid turtle with dark green skin, wearing a red mask across his face and holding the sai that had stopped his wakizashi. He studied his adversary in disbelief. "You're a… turtle!"

"Darn straight!" replied Raphael as he twisted the sai, forcing Mask to let go of his wakizashi. _Must be a new recruit_, he thought. While the red-masked turtle could tell that his enemy wasn't human, he hadn't yet guessed that he was fighting a fellow turtle; the light was _behind _Mask and he was only visible as a darkened silhouette. Not that Raph was particularly interested in _what_ he was fighting at the moment.

Mask backed away slowly. So _these _were Saki's great enemies? Turtles like him? He'd never considered that he _wasn't_ the only one of his kind… even if they _were _as vicious as Saki had said… The wind left Mask as another turtle floored him with a tackle, kneeling on his chest to keep him down. The Foot turtle couldn't fight back; the shock of his realization was paralyzing - and he was still gasping for air.

The Foot ninja were not at home in the sewers, and were almost useless in the sudden confrontation. Don struck out with the butt of his staff and knocked the last one unconscious. "We'll drag 'em to the surface, I guess," he sighed, shouldering his bo.

"Wrong," countered Raph. They've seen us in this tunnel. It gives 'em a place to resume their search… we can't allow that." He spun one of his sai meaningfully.

"We'll worry about that later - I've got a conscious prisoner!" announced Mikey.

"A what? Mikey, get him on his feet and bring him into the light. We'll get to the bottom of this," commanded Leo with a businesslike air.

Mask was silent as Michelangelo forced him to stand and shoved him against the wall in the beam of light. Even Leonardo gasped.

"Is he what I think he is?"

"Saki was wrong," Mask said quietly, mostly to himself. He inspected the features of his four captors. "I see no brutality in their eyes. Even after we try to assassinate them… they only consider killing us because we know dangerous information." He sighed heavily and stared at his submerged feet. "They're not monsters, after all…"

Mikey turned to glance at Raph. The red-masked turtle scoffed at the soft look in his brother's eyes. "Heh. 'S prob'ly an act. Wouldn't put it past one of Shredder's goons."

"_The Shredder_? I don't know any 'Shredder,'…" The brown turtle looked confused. "I served one called Master Saki."

"No way of knowin' that's true," growled Raph, interrupting Mikey as he started to speak. "We don't know, Mikey! He could be _perfectly aware _that Saki and the Shredder are the same guy!"

Leo sighed. "Maybe Master Splinter can make some sense out of this. Don and I will take him back to the lair. Raph, you and Mikey take care of these Foot ninja. I don't really care _what _you do with them."

Don grabbed the tails of the brown turtle's skull mask so the holes no longer lined up with his eyes. "Move, you."

Mask felt like his entire world had been turned on its head. His enemies might as well be his own cousins, and it appeared that Saki had deceived him…at the moment, he didn't really care whether or not death waited at the end of his journey down the sewer tunnel. He walked silently, numbly, with two fellow turtles holding his arms and roughly escorting him along.


	6. Chapter 5

Splinter lay on the couch, sipping a hot cup of tea in satisfaction. His favorite channel was featuring a marathon of his favorite program, and the lair was quiet.

"Master Splinter!"

"Master Splinter!"

The old rat winced slightly. Well, he'd enjoyed it while it had lasted… "Leonardo? Donatello? Where are your brothers?"

"They're disposing of a band of Foot ninja who attacked us just now," Leo reported. "And we found… this." They steered Mask into the TV room.

Splinter sighed inwardly as he turned off his show, but snapped to attention when he noticed the third body. "Why have you brought him here!" His eyes left the Foot symbol now off-center on Mask's forehead and swept the rest of his body. "What…?"

Donatello nodded. "I know…he's a turtle of some sort. Different from us, but still a turtle. And as for serving the Foot, he seems not to know a lot about his master. He didn't know (or pretended not to, anyway) that Saki is also called the Shredder. We wanted to get your input on it, Sensei. He really hasn't said much since we defeated his gang; he seems a bit confused more than anything."

Splinter studied the newcomer, then waved his sons aside. They took a couple of steps back while their rat master came to stand directly in front of the brown turtle. "You may fix your mask, kame." He waited as Mask realigned the holes in front of his eyes. "Now. Tell me how you came to be in the service of the Foot. Look directly into my eyes as you do so."

Mask was surprised as he noticed the giant rat standing before him. They had _those _here, too? But the look in the rat's eye told him to get talking, and fast. "All I know is I was born here in the sewers, and had to leave because there wasn't enough food to eat. I've lived under one of the docks in the harbor for most of my life, and learned to hunt fish with a bow I made myself.

"One night, a group of Foot ninja came sneaking around. I didn't know then who they were. They found me while I was just finishing up my hunt for the night, and seemed surprised - though oddly, it wasn't because I was a giant turtle. Almost as if they expected someone else…"

Leo and Don exchanged glances.

"I woke up in a dark room - one of the ninja had knocked me out. There I met Saki, who told me I could help in his fight against evil monsters in the sewers. He obviously meant you guys."

"Of course," muttered Leonardo.

"Silence!" chided Splinter. Then to Mask, "Continue."

Mask never let his eyes waver from the rat's deep brown ones, wanting to look as far from "shifty" as possible. "He continued my training with this bow, and a bit with my wakizashi. He recently told me the danger had increased; I was sent out, without further training, to rid him of his enemies. Honestly I didn't know what you guys were. I didn't realize you guys _weren't _heartless brutes. I…"

Splinter held a paw up for silence. "That's enough. Leonardo, Donatello… keep an eye on him. I will meditate on the matter." The old rat calmly crossed the lair and entered his own room.

Mask stood still in the silence that followed. Leo and Don remained at either side of him, arms crossed and staring into space. The brown turtle sighed - he felt like he was on trial. Though he didn't blame them for being cautious.

Sounds began filtering from the sewer tunnel outside. Minutes later, Raphael and Michelangelo jogged in. They paused upon seeing Mask in their TV room, but not for long.

"We picked up the weapons he dropped in the tunnel," proclaimed Mikey, the bow under one arm and the bared wakizashi in his other hand. He carried the weapons in and set them on the couch.

"So what's the verdict?" Raph demanded.

Don shrugged. "None yet. Sensei's meditating."

Mask had slowly sunk to the floor, and sat there now with his face in his hands.

Raphael stalked to his side and nudged Mask's left shin with his foot. "What's up with _you_?"

The brown turtle looked up with a distressed expression on his face. "Had I been captured by Saki… You guys don't torture your captives. I… rrrh!" Unable to express his disgust at the realization of what he'd been serving, Mask grabbed the tails of his skull mask and aggressively tore it off. It landed several yards away.

The four brothers' eyes traveled between each other and the scrap of black and red fabric on the floor. They were trying to decide whether to dismiss it as meaningless drama, or soften their instinctive defense against the newcomer.

Heedless of their stares, Mask noticed the black bindings on his limbs as if for the first time. He began to tear at them, feeling filthy with them wrapped around his arms and legs.

"My sons…" began Splinter, sliding the door aside and emerging from his room. He caught sight of Mask, who was busily ripping the black wrappings from his left leg. The old rat smiled. "I have pondered on what I heard from our guest. While I do not know exactly how he came to be mutated, I do know that the truth was shining in his eyes. Look at him now. If he were truly serving the Foot and trying to infiltrate us, he would be checking our reactions from the corner of his eye. Yet look."

Mask was focused only on ridding himself of his Foot garb. Flinging aside the last wrapping, he suddenly felt that he was being watched. Looking up, he was surprised to see the rat had returned. He bowed from his sitting position. "What have you decided?"

Raph stared at him, but with a softer gaze this time. _Poor turtle… he totally blocked him out just now, getting' that Foot crap off._

Leo offered Mask his hand. "Welcome aboard. I am Leonardo, and these are my brothers - Donatello, Raphael, and Michelangelo. Though we usually go by Leo, Don, Raph, and Mike. It's shorter, y'see."

Mask allowed himself to be pulled up. "Donawhatta? Yeah, see what y'mean. I'm called Mask. No cool long name, I'm afraid," He noticed his weapons lying on the couch and picked them up. He sheathed his wakizashi after drying it on one of his discarded wrappings, and unstrung his bow, replacing it on his back.

As Mask put away his weapons, Don had been inspecting a curious piece of equipment that seemed to be clipped to the back of his belt. "Hey, Mask… what's that?"

The brown turtle's hand went back to where Don's gaze was fixed and his eyes widened. "Oh, crap…"

"What is it!" Leo's hand went instinctively to the handle of his katana.

Mask unclipped the device and held it up. "It's a communication thingy. Mostly it's like a long-range walkie-talkie… but it's also used to track us. I can't stay here. Not with this, anyway.

Raph drew his sai almost without thinking. "Well, shut up and let's get out of here!"


	7. Chapter 6

His arms draped over the shoulders of two others, a Foot ninja was hurried through the doors of Oroku Saki's dojo.

Saki halted his practice and stood before the man. "Speak!"

The wounded ninja gasped, "Attacked… in tunnel. They came too close too fast for… ugh… Mask to get off many arrows." He sagged between the supports of his two fellows. "Woke up near a manhole… nowhere near the place we entered the sewers. The others were there; they were all dead…"

Saki's brow furrowed. "And Mask?"

"He wasn't… anywhere. Master, I need… help…" The ninja began to writhe slightly; he'd gained some serious stab wounds.

"Take him away," ordered Saki. Turning to a couple of ninja who stood nearby, he barked, "Get me a team of trackers! I expect the Turtles took him down to wherever they're hiding to figure out what he is. This is our chance to find them, and destroy them!"

* * *

"That's odd - my tracker is indicating Mask is above ground right now… about 300 yards away from here." The leader of the twelve ninja studied the screen on the small device he was holding.

"So… d'you think he was dumped at a different manhole when they were finished with him, Demon?" theorized one of his comrades, using his code name.

"Or they've been tricking us all along into thinking their hideout is underground," mused the leader. "Either way, his communicator is up ahead."

They made one last turn and found themselves facing a dead-end alley lined with dumpsters. "Okay. Half of you check the walls for hidden entrances. The rest, help me search the dumpsters for his body."

Mask lay beneath the lid of the first dumpster, tensing himself for action. When were they going to open the accursed lid? The heat of the decomposing garbage was stifling, to say nothing of the smell… Light suddenly poured in, accompanied by a grinding creak as the lid was lifted high.

The Foot ninja leader bent to peer in… and almost immediately his head snapped back. He fell to the concrete as Mask grabbed the edge of the dumpster and jumped out.

"Mask!" exclaimed one of the dumpster-checking party, thinking the brown turtle had only kicked out in case they were someone else. This misconception was quickly remedied as Mask's palm connected squarely with his nose.

"Don't be upset; we came as quickly as we could…" Demon got up and studied Mask. "Wait… where's your uniform?"

Mask aimed another kick. "If I had my way, it would be stuffed down your throat. Saki - that is, the _Shredder_, is a liar… I'm not having anything more to do with his corrupt gang!"

"Is that so?" The leader easily stopped his kick this time. "So you know about the Shredder and you're defecting?" He sent a series of punches. "Poor choice, Mask!"

Mask sat down hard, clutching his stomach and gasping for air. He didn't have the years of training the Foot ninja had…

The eleven standing ninja closed in around Mask. Demon smirked as he drew his ninja-to. "Poor choice indeed…"

_BANG! BANG!_

The lids of the other two dumpsters were flung open. Demon looked up just in time for his vision to be filled with a huge green foot… For the second time, he hit the pavement hard.

Michelangelo twirled his nunchaku a few times, grinning slightly. "You OKdown there, shellboy?"

Mask winked from his position on the ground. "I really have a lot to learn, don't I?"

The orange-masked turtle laughed. "Just keep your head down! Hyaaaah!"

* * *

EPILOGUE

"Nice block, Mask! Here, try again!"

_Crack!_

The brown turtle fell to the floor but got up, grinning. "Heh, wasn't fast enough that time. Are you _sure _you're OK doing this, Leo?"

"For the thousandth time, yes! Don't worry about it!" sighed the blue-masked turtle. "I offered, didn't I?"

Splinter nodded. "For you to be self-sufficient in battle is better for the safety of us all. It also gives Leonardo a challenge in his own training, for to teach a skill one must perfect it himself."

Raph elbowed Mikey, grinning. "Finally - a hobby for Leo, eh?"

"I thought ninjitsu already was!" The turtle clad in orange chuckled, then looked toward Mask. "Hey… where are you goin'?"

Mask shouldered his bow and headed for the exit to the sewer tunnels. "I must thank you for letting me live on your couch for the past week… and for the training… and for these." He tugged the tails of his new green skull mask, indicating the extra elbow-and kneepads and green wrappings on his limbs. The only Foot-issue items he'd kept were his crossbelts and weapons. "I remember there was a place I noticed when I was, er… hunting you guys. I could fix it up and live there, out of your way."

Raph approached, shaking his head. "We couldn't kick one of our own into the cold, dark sewers! I'm sure we could find a room for ya…"

"No, you guys are _family_. Don't make me intrude on that. It's not like I'm gonna be far away, if you still want to be buddies…"

Raph offered his hand. "There's a question about it? No problem, Mask. Just don't be a stranger!"

"Hey, if you want anything upgraded in your new digs, let me know," wafted Don's voice from the direction of his workroom.

"Yeah, and I'm sure Splinter would be glad to have you at any of our training sessions," added Mikey with a smile.

The brown turtle bowed low. "Thanks for everything… my friends." With that, he turned and was soon sploshing up the sewer tunnel.

THE END

* * *

All right, time for some **end notes**. Just to putthis little storyinto perspective.

First, thanks to all who have read and reviewed. This was a fun tale to sketch out, and I'm glad some have enjoyed it.

Though I admit I _did_ have something of a purpose behind this. There are probably countless "5th Turtle" stories, and while I wanted to write one, I wanted it to play out as "realistically" as possible. Hence, Mask being mutated by the same ooze. With any other mutagen, you are less likely to have the same result (humanoid turtle). I tried to make the "meeting the Turtles" story somewhat feasible as well. Mask (Mud at the time) would have no idea about the TMNT vs. Foot conflict, and wouldn't see the need to hide from anyone save normal humans. If the Foot found a turtle similar to their great enemy, it makes sense that Saki would at the very least want to study it. I was also very careful to make Mask's allegiance to Saki a necessity; he joined only because death would be his reward if he chose otherwise. He obviously saw lots of horrible acts perpetrated by his master, but stayed because of respect for Saki's power and skill. (and because death was still an option if he deserted.) This makes his switch to the Turtles' side much more feasible.

The most important TMNT concept (in _my_ opinion) is their family unity. How they work as brothers (and father) is the thing I like best about them. Which is why I never liked Venus - her addition kinda broke up the "family" attitude. Same thing goes for giving the Turtles girlfriends... while some may adore the idea, I think it interrupts the whole "family" concept. So once I introduced Mask to the Turtles, I couldn't have him live in the Lair for that reason. I didn't want him to interfere with the brotherhood. Instead, he gets to live close by and be a family friend, much like Leatherhead, April, etc. Which, I believe, is for the better.

So yeah. That's it. And if any of you bothered to read that long-winded analysis, you're my hero. Have a cookie.


End file.
